The present invention relates to an image forming apparatus and a method of discarding developer in the image forming apparatus.
A conventional image forming apparatus of an electro-photography type includes a photosensitive drum, a charge roller, an exposure device, a developing device, a transfer roller, and a cleaning member. The charge roller charges the photosensitive drum, and the exposure device forms a static latent image, so that the developing device develops the static latent image to form a toner image. Then, the transfer roller transfers the toner image to a sheet, and a fixing device fixes the toner image followed by discharging the sheet. The cleaning member removes toner remaining on the photosensitive drum after the transfer roller transfers the toner image to the sheet,
In the conventional image forming apparatus of an electro-photography type, when toner remains in the developing device without being developed, toner may be accumulated in the developing device while being deteriorated with time. As a result, toner thus accumulated and deteriorated may cause a trouble such as an uneven density of a printed image, lowering of dot reproducibility, and fog. To this end, a technology has been developed in which toner is discarded after a specific number of sheets are printed (refer to Patent Reference).
Patent Reference: Japan Patent Publication No. 2004-45481
In the conventional image forming apparatus disclosed in Patent Reference, toner is discarded after a specific number of sheets are printed. Accordingly, it is necessary to consume a relatively large amount of toner.
In view of the problems described above, an object of the present invention is to provide an image forming apparatus and a method of discarding developer in the image forming apparatus through discarding toner. In the image forming apparatus of the present invention, it is possible to reduce an amount of toner to be discarded.
Further objects of the invention will be apparent from the following description of the invention.